Mechanistic Insights into a Supramolecular Self‐Assembling Catalyst System: Evidence for Hydrogen Bonding during Rhodium‐Catalyzed Hydroformylation

Abstract

The structural integrity and flexibility provided by intermolecular hydrogen bonds leads to the outstanding properties of the 6-diphenylphosphinopyridin-(2H)-1-one ligand (see scheme) in the rhodium-catalyzed hydroformylation of terminal alkenes, as demonstrated by the combination of spectroscopic methods and DFT computations. Hydrogen bonds were also detected in a competent intermediate of the catalytic cycle.

Anionic phosph(in)ito (“phosphoryl”) ligands: Non-classical “actor” phosphane-type ligands in coordination chemistry

“…In coordination transition metal chemistry, O−anionic  1 -P−phosph(in)ito ligands of general formula {P(O)R 1 R 2 } have similar properties. In recent work reported by Breit and co-workers, the concept of designing supramolecular bidentate ligands by utilizing hydrogen-bond interactions between substituents on two respective monodentate ligands has been realized [174,175]. We previously mentioned, in section 2.3.…”

Rhodium Pyrrolylphosphine Complexes as Highly Active and Selective Catalysts for Propene Hydroformylation: The Effect of Water and Aldehyde on the Reaction Regioselectivity

“…Therefore, extensive research has been devoted to the design of new ligands to enable the selective production of linear aldehydes and then linear alcohols . Theoretical studies on the effect of ligands on the hydroformylation reaction have made important contributions to this field …”

“…[1][2][3][4][5][6][7] Theoretical studies on the effect of ligandsonthe hydroformylation reaction have made important contributions to this field. [8][9][10][11][12][13] The catalytic systemsu sed most frequently for hydroformylation contain Rh I precursors and modifying Pl igands used in excess relative to Rh. Mono-and bidentate ligandsthat contain terminal or internal double bonds and different substituents and functional groups have been applied in the hydroformylation of olefinic substrates.…”

Inducing Axial Chirality in a Supramolecular Catalyst

“…[29,30] Our group has previously developed self-organizing ligand systems based on self-assembly of monodentate building blocks through hydrogen bonding (6-DPPon = 6-diphenylphosphino pyridone,see Scheme 2f or R = Ph and S* = H), [31] and these bidentate ligands were successfully employed in hydroformylation and hydrocyanation of alkenes. [31][32][33][34] We also developed self-organizing ligands with chiral P-donors based on complementary hydrogen-bonding motifs inspired by AT base pairs in DNA. [22,35,36] These ligands were evaluated in the rhodium-catalyzed, asymmetric hydrogenation of a-dehydro amino acids by employing an iterative deconvolution strategy.In the X-ray structures of platinum complexes of the 6-DPPon ligand, we noticed that the supramolecular backbone is not planar,asinthe free ligand dimer, but twisted.…”